I just wanted to know how to analyse a jazz piece. I've done it a few times for classical/romantic music, but I'm new to jazz.

I'm trying to do an analysis of Maria Schneider's 'Evanescence' piece (beautiful).
I'd like to know about rehearsal letters (distinguishing them is hard for me), any key changes, time signature changes (none that I'm aware of)., maybe a light harmonic analysis? I know that it is a tribute to Gil Evans and is also has some of his stylistic influences, but I can't really determine what those are...any help would be greatly appreciated!